Fan scroll



FAN SCROLL Filed Dec. 12, 1968 INVENTOR. WALTE R EAR HART United StatesPatent O 3,485,443 FAN SCROLL Walter Earhart, La Crosse, Wis., assgnorto The Trane Company, La Crosse, Wis., a corporation of Wisconsin FiledDec. 12, 1968, Ser. No. 783,367 Int. Cl. F0411 39/12; F04d 17/08, 29/42U.S. Cl. 230-233 8 Claims ABSTRACT OF THE DISCLOSURE A fan scroll forunit ventilators and similar apparatus combines the function of soundattenuation with structural support through the use of aself-supporting, substantially rigid, sound attenuating material, suchas resin-bonded glass fibers.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to fluid moving fans, and more particularly, to a novel fanscroll assembly for use with centrifugal and cross-flow fans.

Description of the prior art In room heating, Ventilating, and coolingequipment installed in classrooms, hospitals, apartment buildings andsimilar structures, the use of centrifugal or cross-flow fans is commonto circulate the air throughout the room being conditioned. Since airmovement using this type of fan creates undesirable sound levels, it hasbeen the practice to employ some type of sound deadening material in thefan structures. This sound deadening material or insulation is normallyplaced around or combined with the fan scroll which surrounds the fanrotor. In the past, this sound deadening material has not beenassociated with SUMMARY OF THE INVENTION The instant invention providesa fan scroll assembly comprising a scroll portion composed of aself-supporting, substantially rigid, sound attenuating material, thescroll portion being the major structural member of the scroll assembly;the fan assembly further comprises a pair of end plates having intakeports therein and fastening means for securing the end plates againstopposing sides of the scroll. The scroll is preferably made from glassfibers bonded together by a suitable resin and contains ra fluidimperforate layer, for example, a sheet of polyethylene which is locatedintermediate the inner and outer surfaces of the fan scroll.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE l is an exploded perspectiveview of the fan scroll assembly of the instant invention.

FIGURE 2 is a vertical cross sectional view of the fan scroll.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGURE l, fanscroll 1 is molded from a self-supporting, substantially rigid, soundattenuating ice material. End plates 2 and 3 are provided which fitagainst the side portions of fan scroll 1. Flanges 4 fit around theouter edge of the fan scroll. Fastening rods 5 are inserted througheyelets 6 on each of the end plates 2 and 3. The end plates are securedtightly against the side portions of fan scroll 1 by inserting clips 7onto the portions of rods 5 which extend through eyelets 6 on end plate2. Clips 7 are of the spring fastening type; however, threads can beprovided on rods 5, and screw type fasteners can be used in place of thespring clips 7.

The end plates 2 and 3 can be stamped steel stock, molded rigidpolymeric material, or can be manufactured or molded from the samematerial of which the fan scroll 1 is composed. Flanges 8 and 9 areprovided on end plates 2 and 3 to secure the fan scroll assembly to aninstallation surface; for example, the fan board of a unit ventilator.Air inlet orifices 10 and 11 are provided in each of the end plates 2and 3. A rotor assembly connected to a suitable driving means (notshown) can be placed inside scroll 1 when the scroll assembly isinstalled.

Of course, the scroll shape depicted in FIGURE 1 is not the onlyconfiguration in which the instant invention can be utilized. Suitablemodifications can be made to the scroll and end plates to enable it tobe used in a cross-flow fan or other air handling equipment whichrequires a housing.

In reference to FIGURE 2, a cross sectional view of the fan scroll isillustrated. In the preferred embodiment the fan scroll is molded fromglass fibers, shown as 15, which are bound together by a suitable resin,shown as 16. To reduce friction and also to eliminate airflow throughthe insulating material, a neoprene coating is applied to surfaces 17and 18, although for effective operation of the instant inventionneither is necessary. As the fan scroll is being molded, a sheet ofpolymeric material 19 is positioned between the inner and outer surfacesof the scroll. In the preferred embodiment a polyethylene sheet isemployed.

Other rigid, self-supporting insulating materials which can be usedinstead of resin-bonded glass fibers are foamed polyethylene orpolystyrene. Requisite-s of the scroll material are that it be able towithstand the temperatures associated with its application in unitventilators or similar equipment and that it be sufficiently rigid toform the major structural member of the fan scroll assembly.

Other coatings for surfaces 17 and 18 include polychloroprenes, vinyl,polyethylene, paper, oil, or other material which -would inhibit thefiow of fluid through the fan scroll. The sheet-like layer 19 inside thefan scroll can similarly be made from paper, polychloroprene (forexample, poly-z-chlorobutadiene), vinyl, foil, or other materials ableto withstand the molding temperatures Iand the temperatures of theparticular scroll application. Suitable binder resins for the glassfibers are polyesters, epoxys, for example, an amine curedBisphenol-A-epichlorohydrin, silicone resins, polyamides, acrylics,polyvinylacetate, and polystyrenes, for example, a polymethylstyrene.The materials set forth above are not intended to be exhaustive of thosewhich can be utilized in the instant invention. They are merely intendedto be representative.

The utility of this invention is apparent from the foregoing disclosure.Therefore, what is claimed is:

1. A fan scroll assembly comprising `a scroll portion composed of aself-supporting, substantially rigid, sound attenuating material, saidscroll portion being the major structural member of said scrollassembly, said fan assembly further comprising a pair of end plateshaving intake ports therein, and fastening means for securing said endplates against opposing sides of said scroll.

2. The fan scroll assembly of claim 1 wherein the said scroll includes auid imperforate layer.

3. The fan scroll assembly of claim 2 wherein said fluid imperforatelayer comprises a polymeric sheet contained -as an integral part of saidscroll and located intermediate the inner and outer surfaces of saidscroll.

4. The fan scroll assembly of claim 2 wherein said fluid imperforatelayer comprises a resinous coating on at least one of the inner 4andouter surfaces of said scroll.

5. The fan scroll assembly of claim 2 wherein the scroll consistsessentially of glass fibers bound together in a substantially rigid formwith a resinous binder.

6. The fan scroll assembly of claims 2 and 5 wherein said end platesinclude bracket means for mounting said fan scroll assembly.

7. The fan scroll assembly of claim 2 wherein the scroll consistsessentially of a foamed polymeric material.

8. The fan scroll assembly of claim 3 wherein said scroll contains anadditional uid imperforate layer comprising a resinous coating 0n atleast one of the 4inner and outer surfaces of said scroll.

References Cited UNITED STATES PATENTS 2,465,625 3/1949 Ave 23o-1273,018,736 1/1962 c1ay 10s-114 XR 0 3,395,775 8/1968 smith 23o-233 XRROBERT M. WALKER, Primary Examiner U.S. Cl. X.R.

